*,
*::after,
*::before {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  background: #fff;
  color: #000;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 1rem;
  line-height: 1.618;
  display: flex;
  flex-flow: column nowrap;
  min-height: 100vh;
}

.header,
.footer,
.result {
  width: min(calc(100vw - 2rem), calc(1200px - 2rem));
  margin-left: auto;
  margin-right: auto;
}

.preview,
.settings {
  width: min(calc(100vw - 2rem), calc(1200px / 2 - 2rem));
  margin-left: auto;
  margin-right: auto;
}

@media screen and (min-width: 1200px) {
  .preview {
    margin-right: 0;
  }

  .settings {
    margin-left: 0;
  }
}

.header {
  padding: 2rem 0 3rem;
  text-align: center;
}

.branding {
  color: hsl(219, 64%, 35%);
}

.main {
  flex: 1;
  display: flex;
  flex-flow: row wrap;
  gap: 1rem;
  margin: auto;
}

.preview {
  border: 1px solid #ccc;
  padding: 3rem;
  position: relative;
}

.box {
  border: 1px solid #000;
  width: 100%;
  height: 20vh;
  position: sticky;
  top: 3rem;
}

.result {
  max-width: 100%;
}

.result__pre {
  background: #333;
  color: #fff;
  min-height: 20rem;
  margin: 1rem auto;
  padding: 0 1rem;
  overflow-x: auto;
  tab-size: 4;
}

.result .btn {
  margin: auto;
}

@media screen and (min-width: 1440px) {
  .result__pre {
    margin: 1rem 0;
  }
}

.footer {
  margin-top: 2rem;
  padding: 1rem 0;
}

.copyright {
  font-size: 0.9rem;
  text-align: center;
}

.form p {
  font-weight: 600;
}

.form__fieldset {
  border-color: hsl(219, 64%, 35%);
  margin-bottom: 1rem;
  padding: 0.5rem 1rem 1rem;
}

.form__fieldset--flex {
  display: flex;
  flex-flow: row wrap;
  gap: 1rem;
}

.form__legend {
  color: hsl(219, 64%, 35%);
  font-size: 0.9rem;
  font-weight: 600;
  text-transform: uppercase;
  padding: 0 0.5rem;
}

.form__item--flex {
  display: flex;
  flex-flow: column wrap;
}

.form__item:not(.form__item--flex) + * {
  margin-top: 1rem;
}

.form__input,
.form__select {
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
}

.form__input {
  padding: 0.2rem 0.5rem;
}

.form__select {
  padding: 0.4rem 0.5rem;
}

.btn {
  background: #fff;
  border: 2px solid hsl(219, 64%, 35%);
  box-shadow: 1px 1px 2px hsl(219, 64%, 15%), 0 0 2px 1px hsl(219, 64%, 15%);
  color: hsl(219, 64%, 35%);
  font-family: inherit;
  font-size: inherit;
  font-weight: 600;
  line-height: inherit;
  display: block;
  padding: 0.5rem;
  cursor: pointer;
  transition: all 0.15s ease-in-out 0s;
}

.btn:hover,
.btn:focus {
  background: hsl(219, 64%, 35%);
  color: #fff;
}

.btn:active {
  transform: translateX(1px) translateY(1px);
}